The semi-official China News Service (CNS) quoted a Communist Party chief as saying some acrobats "stayed behind".

Canadian news reports say the seven acrobats - five men and two women - hoped to stay in Canada and filed refugee claims in Toronto last week.

The acrobatic troupe was in Canada as part of Chinese New Year festivities.

It was not clear if the Canada would give the group refugee status.

The CNS quoted Wang Lequan, Xinjiang's Communist Party chief, as saying the group "did not know the truth and were deceived by overseas separatists".

"They are welcome to return to the motherland and return to their warm families," he said.

The CNS said the head of the delegation would remain in Canada to work with the Chinese embassy there and Canadian authorities to find the acrobats.

Mr Wang did not say how many had defected but another official in Xinjiang later told the Reuters news agency that seven of the acrobatic group had stayed behind.

Xinjiang's native Muslim population, known as Uighurs, are Turkic speaking, and are ethnically and linguistically distinct from China's Han majority.